Method and Device for Maintaining Constant Moisture Level in Cleaning Cloths

ABSTRACT

This invention relates to a method and device for maintaining an optimum dampness level in preconditioned cleaning cloths for extended periods of time while still enabling repetitive retrieval and use of individual cloths. The device described herein maintains an environment where the temperature and humidity of the vapor surrounding the cloths are stored to a preset level, thereby minimizing moisture change. The invention is applicable to any cleaning operation requiring repetitive small-batch operations over an extended period of time, but is especially useful for such operations such as window cleaning in commercial car washes and food service establishments.

REFERENCES (INCORPORATED HEREIN BY REFERENCE)

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not applicable.

MICROFICHE APPENDIX

Not applicable.

FIELD OF THE INVENTION

This invention relates to a method and device for maintaining the effectiveness of preconditioned cleaning cloths. Particularly, this invention relates to preconditioned cleaning cloths used in facilities that practice repetitive cleaning of hard surfaces. More particularly, this invention pertains to hard surface cleaning methods used in car wash and food service facilities and devices for storing the cloths whereby their effectiveness can be maintained for indefinite periods of time.

BACKGROUND

Facilities that practice repetitive surface cleaning, such as commercial car wash facilities, require a large number of cleaning and drying cloths on a continuing basis. In general, the cleaning cloths must effectively be treated in some manner with a liquid solution prior to cleaning. In many cases this is done immediately preceding the act of cleaning, either by applying the solution directly to the cloth or by applying the solution directly to the surface or both. In all cases, the act of cleaning requires the cloth to absorb the solution and, through a wiping process, distribute the solution over the entire surface to be cleaned, thereby loosening or dissolving the unwanted material to be removed. The unwanted material plus the solution, which now acts as a carrier, are then removed either by rinsing, wiping with a drying cloth or by use of a flat, surface-conforming blade. However, in interior situations the use of rinsing is generally not practical. Moreover, if the surface to be cleaned is not sufficiently flat in shape and/or has even minor surface texture, removal by a conformal blade is not efficacious. Therefore, convention is to use drying cloths.

A disadvantage of the cleaning methods described above, whereby the cleaning fluid is applied either to the cloth or to the surface to be cleaned, is that the cleaning fluid, generally applied via spray, is not applied evenly, whether first applied to the cloth, the surface to be cleaned or both. As has been described previously in U.S. Pat. No. 7,793,373, this results in surfaces that have not been adequately cleaned, as evidenced by streaks, smears and smudges of residue. One solution to this problem, disclosed in U.S. Pat. No. 7,793,373, is to pre-condition the cloths with cleaning fluid so as to evenly distribute the fluid throughout the cloth. U.S. Pat. No. 7,793,373 further teaches that if a the cloth is preconditioned with an optimum amount of cleaning fluid, no or minimal post wiping with a drying cloth is necessary, thereby removing a step in the cleaning process and improving efficiency. Further, U.S. Pat. No. 7,793,373 teaches that the optimal preconditioning can be accomplished for large quantities of cloths simultaneously by carrying out the preconditioning in a commercial washing machine where the cleaning agent is added to the final rinse cycle and then the optimum level of cloth dampness is obtained through adjusting the speed and time of the spin cycle to leave the right amount of cleaning fluid evenly distributed in the cloth.

A new problem that arises from this method is how to store the preconditioned cloths so as to retain the optimum cloth dampness. Commonly, the cloths are stored in a closed container to impede moisture escape. However, with repeated opening of the container and the resulting losses of vapor the dampness of the cloths gradually decreases, especially in those cloths nearest to the top of the container. Some operators of commercial carwashes try to compensate for this by adjusting the spin cycle to achieve a higher initial dampness. However, this method results in poorer initial cleaning and the tendency for excess fluid to migrate into the cloths stored near the bottom, which in turn, results in streaking. A further improvement on this method is to store the pre-moistened cloths in a container, which includes a fluid reservoir to replace vapor losses with opening. However, this solution can lead to over saturation of the cloths from continual condensation within the container and over saturation of the ambient atmosphere within the container. Clearly, an improvement in the overall process would be an advance in the art.

SUMMARY OF INVENTION

The principle aim of the invention herein to improve the efficacy and efficiency of cleaning hard surfaces.

Another aim of the invention herein is to provide a storage method and device for preconditioned cloths, which serves to retain their dampness level within an optimum range for extended periods of time while still enabling repetitive retrieval and use of individual cloths.

To effect the aims of the invention, a storage container is described which maintains a constant vapor of conditioning fluid over and around the cloths in order to impede evaporative loss and maintain an even distribution of moisture throughout all of the cloths. The container is insulated and contains a reservoir of fluid, separated from direct contact with the cloths, which provides a constant source of vapors. In addition, the relative humidity in the chamber can be controlled through the use of a heating element within the reservoir in combination with temperature and humidity sensors within the container. Adjustable vents can be incorporated into the sides of the unit allow for the escape of excess humidity and better humidity control.

In one embodiment, the container includes a regulated heater for maintaining a constant internal temperature. This serves to accelerate vapor replacement when the container is opened and helps maintain a constant vapor level with temperature changes.

In another embodiment, the fluid reservoir is positioned directly beneath the cloths and kept separated from them by a waterproof grating or perforated shelf.

In another embodiment, the cloths are kept separated from the fluid reservoir by a waterproof grating in the form of a basket, which keeps them separated from the sides of the container.

In another embodiment, the storage container includes adjustable vents to aid the escape of excess humidity without necessitating the opening of the lid.

In another embodiment, the storage container includes a humidity and temperature sensor, with or without display, and control unit to enable the user to set and maintain a specific temperature and humidity level.

DRAWINGS

FIG. 1. FIG. 1 shows the storage container supplied with grating and temperature/humidity display in accordance with one embodiment.

FIG. 2. FIG. 2 illustrates the optional basket with multiple circular perforations in accordance with one embodiment.

FIG. 3. FIG. 3 shows the storage container with grate removed, revealing possible placements of the heater and the temperature/humidity sensor in accordance with one embodiment.

FIG. 4. FIG. 4 shows one embodiment of the heating element, including the electrical cord and variable control.

FIG. 5. FIG. 5 shows a front view of the storage container showing one possible position of the fluid reservoir, directly below the grating.

FIG. 6. FIG. 6 shows one example of a temperature/humidity control module with connection cords to an electrical outlet, a heating unit and to a temperature/humidity sensor.

FIG. 7. FIG. 7 shows a graph of moisture retention in preconditioned cloths depending on storage conditions. Cloths in the control case were kept in a storage container with no cleaning solution in the reservoir. Cloths stored in condition A were kept in a storage container with cleaning solution in the reservoir and maintained at a temperature of 90° F.

REFERENCE NUMERALS

8. Container lid

9. Grate

10. Handle

11. Temperature/Humidity display and control module with power cord

12. Container base

13. Electrical cord for heater and control module

14. Humidity and temperature sensor

15. Heating element

16. Lid recess.

17. Optional basket

18. Variable control for heater

20. Fluid reservoir

22. Vents

DESCRIPTION OF INVENTION

The invention herein relates to a method and device for maintaining an optimum dampness level in preconditioned cleaning cloths for extended periods of time while still enabling repetitive retrieval and use of individual cloths. The cloths herein may be taken to mean any absorbent towel, cloth or other fabric suitable for cleaning hard surfaces. The invention is applicable to any cleaning operation requiring repetitive small-batch operations over an extended period of time, but is especially useful for such operations such as window and car-body cleaning in commercial car washes and food service establishments.

With reference to FIG. 1 for purposes of illustration, the present invention is embodied in a storage container that maintains a constant vapor of conditioning fluid over and around the cloths in order to impede evaporative loss and maintain an even distribution of moisture throughout all of the cloths. The container comprises an insulated base 12, close-fitting lid 8, and grate 9 that keeps the cloths separated from the reservoir of fluid that, in this case, is located in the bottom of the base 12. In a preferred embodiment, the storage container includes any combination of the following features: handles 10 for ease of transport; a finger recess 16 in the lid 8 for ease of opening; a temperature and humidity display and control module 11; vents 22 for release of excess humidity; and an electrically controlled heating element. It should be noted that the relative positions of the individual parts of the storage container as shown in FIG. 1 and in subsequent figures represent just one of many acceptable positions are not intended to be specifically required for functioning of the storage container unless specifically stated.

With reference to FIG. 2, the grate 9, which is shown in most of the illustrations as a flat shelf or grating with perforations to allow free flow of vapors from the reservoir to the cloths, may optionally be in the preferred form of a basket 17. In either case, the function of the grate is simply to hold the cloths away from direct contact with the cleaning fluid in the reservoir while simultaneously allowing the cleaning fluid vapors to freely intermingle with the cloths. The perforations may be of any convenient shape and size so as to achieve this objective while not being so large as to allow cloths or any portion of the cloths to fall through and reach the fluid in the reservoir.

FIG. 3 illustrates one embodiment of the storage container, in which the grate has been removed for clarity, which includes a regulated heating element 15 for maintaining a constant temperature of the fluid in the reservoir and of the vapor within the storage container. The heating element is most conveniently controlled electronically and, therefore, includes an electrical cord 13 for connection to a controller and source of electricity. The controller may be a manually adjusted controller, as shown, or may optionally be controlled by a separate control module 11. Without wanting to be bound by theory, the heating element, by maintaining an elevated temperature within the cleaning fluid, serves to accelerate vapor replacement when the container is opened and helps maintain a constant vapor level with temperature changes. Also shown in FIG. 3 is an optional internally mounted temperature and humidity sensor 14 which can be used to send data to an externally mounted display and control module 11. The display and control module 11 may optionally regulate the electrical current to the heating element through means of a specially programmed integrated circuit board as an alternate and more direct means to enable the user to set and maintain a specific temperature and humidity level. This represents the preferred embodiment.

FIG. 4 illustrates one configuration of the heating element 15 showing the electrical cord and integrated variable control 18, which, in this case, plugs directly into an electrical socket. As stated previously, the heater may optionally connect directly to a separate control unit, which may be programmable.

FIG. 5 illustrates the positions of the grate 9, heating element 15 and temperature and humidity sensor 14 relative to the reservoir 18. The heating element 15 is positioned so as to be immersed within the cleaning fluid and, therefore, inside the reservoir 18, whereas the grate 9 is slightly above the reservoir and is thus able to keep the cloths separate from the cleaning fluid. The temperature and humidity sensor is positioned to be above the reservoir so as to read the conditions of the vapor within the storage container. The relative positioning of these parts as shown in FIG. 5 are but one of the acceptable relative placements for the heating element 15, temperature and humidity sensor 14, and grate 9, so long as the heating element 15 is always maintained in direct contact with and preferentially immersed in the cleaning fluid in the reservoir 18, the grate 9 is positions so as to keep the cloths separate from the cleaning fluid and the temperature and humidity sensor 14 is kept out of direct contact with the cleaning fluid but inside of the storage container.

FIG. 6 shows one example of an acceptable humidity and/or temperature control module. Such modules are readily available commercially, as for example,

As a demonstration of the effectiveness of the storage container, a set of six waffle weave, lint-free, cleaning cloths were saturated with an aqueous solution of 25% by volume Hot Glass® window cleaning solution, supplied by Panaram International, and their moisture retention was measured versus time under two conditions. In each case, the initial amount of cleaning fluid was controlled to an optimum level for streak-free cleaning of approximately 45% by weight cleaning solution relative to the entire cleaning cloth. In the first experiment, hereafter referred to as the “control”, the cloths were placed in a storage container as described above that contained no cleaning solution in the reservoir and which was kept at ambient temperature. In the second experiment, hereafter referred to as “condition A”, the preconditioned cleaning cloths were placed in the same storage container but this time containing cleaning fluid in the reservoir which was maintained at a relatively constant temperature of 90° F. The weight of cleaning solution in the towels was in both cases measured periodically throughout a period of approximately 150 hours. The results, shown in the chart in FIG. 7, demonstrate the superior moisture retention of the towels in condition A as compared to the control. In fact, after a period of almost 150 hours, the towels in condition A were still effective in leaving streak-free surfaces when used for cleaning, whereas those of the control were too dry to be effective. 

1. A method of keeping cleaning cloths conditioned with a prescribed amount of cleaning fluid comprising placing the cloths into a closeable, insulated container which contains a reservoir of cleaning fluid separate from the cleaning cloths which allows vapors from the cleaning fluid to continually permeate the cleaning cloths.
 2. A method according to claim 1 wherein the cleaning fluid reservoir is kept immediately beneath the cloths.
 3. A method according to claim 2 wherein the cloths are kept separated from the fluid in the reservoir by a flat grating or perforated shelf made of any suitable water-resistant material.
 4. A method according to claim 2 wherein the cloths are kept separated from the fluid in the reservoir by means of a basket-shaped grating or perforated basket made of any suitable water-resistant material.
 5. A method according to claim 1 in which the cleaning fluid contains a disinfectant.
 6. A method according to claim 1 in which the closeable, insulated container referenced therein includes a heating unit in the fluid reservoir which can be set to maintain the fluid and the atmosphere within the container to a specific temperature.
 7. A method according to claim 6 in which the heater heating unit can be set to a temperature between 40F and 150F.
 8. A method according to claim 6 in which the closeable, insulated container includes a temperature and humidity sensor with external display and control module.
 9. A method according to claim 8 in which the temperature and humidity sensor are connected electronically through a control board to adjust fluid temperature, as necessary, to maintain a consistent relative humidity level and desired cloth temperature.
 10. A device for keeping cleaning cloths conditioned with a prescribed amount of fluid comprising a closeable, insulated container, a reservoir of cleaning fluid separated from the cleaning cloths by a grate or basket, a heating device for maintaining the fluid at a prescribed temperature, vents to aid in the escape of excess humidity and a control module for setting and maintaining a prescribed temperature and humidity level. 